Related Experiment Video
Updated: Apr 25, 2026
A TIRF Microscopy Technique for Real-time, Simultaneous Imaging of the TCR and its Associated Signaling Proteins
Published on: March 22, 2012
Phosphorylation site dynamics of early T-cell receptor signaling
Lily A Chylek1, Vyacheslav Akimov2, Jörn Dengjel3
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America; Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, United States of America.
Abstract:
In adaptive immune responses, T-cell receptor (TCR) signaling impacts multiple cellular processes and results in T-cell differentiation, proliferation, and cytokine production. Although individual protein-protein interactions and phosphorylation events have been studied extensively, we lack a systems-level understanding of how these components cooperate to control signaling dynamics, especially during the crucial first seconds of stimulation. Here, we used quantitative proteomics to characterize reshaping of the T-cell phosphoproteome in response to TCR/CD28 co-stimulation, and found that diverse dynamic patterns emerge within seconds. We detected phosphorylation dynamics as early as 5 s and observed widespread regulation of key TCR signaling proteins by 30 s. Development of a computational model pointed to the presence of novel regulatory mechanisms controlling phosphorylation of sites with central roles in TCR signaling. The model was used to generate predictions suggesting unexpected roles for the phosphatase PTPN6 (SHP-1) and shortcut recruitment of the actin regulator WAS. Predictions were validated experimentally. This integration of proteomics and modeling illustrates a novel, generalizable framework for solidifying quantitative understanding of a signaling network and for elucidating missing links.
Insights
This study reveals rapid, dynamic changes in T-cell signaling proteins within seconds of stimulation. Quantitative proteomics and computational modeling identified novel regulatory mechanisms in T-cell receptor (TCR) signaling.
Area of Science:
- Immunology
- Cellular Signaling
- Proteomics
Background:
- T-cell receptor (TCR) signaling is crucial for adaptive immunity, controlling T-cell differentiation, proliferation, and cytokine production.
- Understanding the systems-level dynamics of TCR signaling, particularly in the initial seconds, is limited despite extensive study of individual interactions.
Purpose of the Study:
- To characterize the dynamic reshaping of the T-cell phosphoproteome following TCR/CD28 co-stimulation.
- To develop a computational model for understanding early TCR signaling dynamics and identifying novel regulatory mechanisms.
Main Methods:
- Quantitative proteomics was employed to analyze phosphoproteome changes.
- A computational model was developed and used for prediction generation.
- Experimental validation was performed to confirm model predictions.
Main Results:
- Diverse phosphorylation dynamics were observed within seconds of TCR/CD28 co-stimulation.
- Widespread regulation of key TCR signaling proteins occurred by 30 seconds.
- The model predicted and experiments validated novel roles for PTPN6 (SHP-1) and WAS in TCR signaling.
Conclusions:
- The integration of proteomics and computational modeling provides a powerful framework for quantitative analysis of signaling networks.
- Novel regulatory mechanisms, including the roles of PTPN6 and WAS, were elucidated in early T-cell activation.
- This approach offers a generalizable method for understanding complex cellular signaling pathways.
Related Concept Videos
01:26Receptor Tyrosine Kinases
01:22Amplifying Signals via Enzymatic Cascade
01:30Assembly of Signaling Complexes
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
01:16TGF - β Signaling Pathway
01:02Phosphorylation
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...
01:02Phosphorylation